Commit 6f9dc684 authored by Samuel Holland's avatar Samuel Holland Committed by Andrew Morton
Browse files

scs: add CONFIG_MMU dependency for vfree_atomic() 

The shadow call stack implementation fails to build without CONFIG_MMU:

  ld.lld: error: undefined symbol: vfree_atomic
  >>> referenced by scs.c
  >>>               kernel/scs.o:(scs_free) in archive vmlinux.a

Link: https://lkml.kernel.org/r/20240122175204.2371009-1-samuel.holland@sifive.com


Fixes: a2abe7cb ("scs: switch to vmapped shadow stacks")
Signed-off-by: default avatarSamuel Holland <samuel.holland@sifive.com>
Reviewed-by: default avatarSami Tolvanen <samitolvanen@google.com>
Cc: Will Deacon <will@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent e4e3df29

arch/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -673,6 +673,7 @@ config SHADOW_CALL_STACK 
	bool "Shadow Call Stack"

	depends on ARCH_SUPPORTS_SHADOW_CALL_STACK

	depends on DYNAMIC_FTRACE_WITH_ARGS || DYNAMIC_FTRACE_WITH_REGS || !FUNCTION_GRAPH_TRACER

	depends on MMU

	help

	  This option enables the compiler's Shadow Call Stack, which

	  uses a shadow stack to protect function return addresses from